Unit 6: Gene Expression and Regulation Flashcards
cell
basic unit of all life
protein
complex structures made of a chain of amino acids folded together; used for structure, function, and regulation of cells
histone
proteins that DNA is wrapped around in
double helix
the structure of DNA
DNA Replication
process by which DNA is replicated in a cell
transcription
producing mRNA from DNA
translation
producing proteins from mRNA
gene
sections of DNA that code for proteins and associated traits
genetic engineering
use of biotechnology to maniplate an organism’s genome
nitrogenous base
serves as the main coding for DNA; includes A, T, U, C, and G
nucleotide
monomer of nucleic acids, containing a sugar, a phosphate, and a nitrogenous base
nucleic acid
genetic material formed from nucleotides that is either DNA or RNA
Ribonucleic Acid (RNA)
nucleic acid with only one helix with many functions as in mRNA, tRNA and rRNA
deoxyribose
5 carbon sugar found in DNA that is missing and oxygen
ribose
5 carbon sugar found in RNA
3’ end of DNA
end of DNA containing a hydroxyl (OH) group where new nucleotides are added
5’ end of DNA
end of DNA containing a phosphate group
DNA polymerase
builds new segments of DNA
RNA polymerase
enzyme that transcribes DNA to make mRNA strand
amino acid
monomer of proteins
messenger RNA (mRNA)
spliced product of DNA transcription that sends genetic information to ribosimes for protein synthesis
transfer RNA (tRNA)
RNA that attatches appropriate amino acids to make proteins
ribosomal RNA (rRNA)
structural RNA in the ribosome
semiconservative model of DNA replication
states that DNA replication occurs by the unwinding of it into two halves and then the adding of strands to both halves
replication fork
split structure formed during DNA replication on both sides of a replication bubble
template strand
strand that is “read off” of by RNA polymerase to transcribe a copy of the coding strand
antiparallel
two helices of DNA are parallel to each other but run in opposite directions
helicase
enzyme that “unwinds DNA”
topoisomerase
enzyme that holds DNA strands apart to tension in strands during replication
ligase
glues okazaki fragments together
introns
noncoding regions of pre mRNA that are spliced off
exons
coding regions of pre mRNA that remain after splicing
codon
three consecutive bases on mRNA that code for one amino acid
splicing
the process of removing introns from pre mRNA to form a final mRNA product
anticodon
three spots on a tRNA that go with a specific codon sequence on mRNA
gene expression
process by which DNA codes for proteins
operon
strand of DNA in prokaryotes required for enzyme production
transcription factor
proteins that control whether a gene will be transcribed and to what extent it will be transcribed
promoter
site on DNA where RNA polymerase can bind to start transcribing
operator
“on and off” switch in prokaryote DNA that controls whether or not genes will be transcribed
repressor
protein that attaches to the operator to block RNA polymerase from transcribing a gene
regulatory gene
gene that codes for a repressor protein
inducible operon
operon that is usually off but can be “induced” on
repressable operon
operon that is usually on but can be “repressed” to turn off
virus
pathogen with RNA that replicates only inside a living organism
biotechnology
use of organisms or their components to produce useful products
gel electrophoresis
method of sorting DNA
DNA sequencing
figuring out the nucleotide sequence of DNA using DNA fragments
Polymerase Chain Reaction (PCR)
used for duplicating a DNA strand
conjugation
exchange of plasmid genes between bacteria
epigenetics
study of how traits and behaviors acquired through an organism’s lifetime can affect the traits of the offspring
triploidy
an extra set of chromosomes
cell differentiation (cell specialization)
how cells gain roles or functions in the body
What structures are involved in passing hereditary information from one generation to the next?
DNA and sometimes RNA
What characteristics of DNA allow it to be used as the hereditary material?
it has a specific nucleotide-based pairing that is conserved through evolution
What are the mechanisms by which genetic information is copied for transmission between generations?
DNA replication
What are the mechanisms by which genetic information flows from DNA to RNA to protein?
Transcription, splicing, and translation
How is the phenotype of an organism determined by its genotype?
The genotype consists of genes that code for proteins which then make up your phenotype
What types of interactions regulate gene expression?
In prokaryotes: regulatory genes, repressor proteins, promoter, operator, inducer
In eukaryotes: promoter (ex: TATA box), transcription factors (activators and repressors), terminators
How does the location of regulatory sequences relate to their function?
Regulatory sequences are near the genes that they regulate, hence providing their function
How does the binding of transcription factors to promoter regions affects gene expression and/or the phenotype of the organism?
transcription factors can either promote the transcription of a gene (activators) or inhibit the transcription of them (repressors), both of which make or stop making proteins that affect determine the phenotype of the organism
What is the connection between the regulation of gene expression and phenotypic differences in cells and organisms?
regulation of gene expression determines whether proteins are made or not which determines the phenotype differences in organisms
What are the various types of mutations?
- point mutations = change in a single nucleotide pair of a gene
- nucleotide substitution = wrong nucleotide is substituted for the original one
- frameshift mutation = shifts the entire nucleotide sequence by a few nucleotides
- insertion = adding nucleotides
- deletion = removing nucleotides
- nonsense mutation = mutation changes codon into a stop codon
- missense mutation = mutation changes codon to code for a different amino acid
- silent mutation = point mutation does not change the amino acid coded for
- duplication = nucleotide sequence is duplicated
- inversion = nucleotide sequence is inverted
- translocation = nucleotide sequence is transferred to another chromosome
How do alterations in DNA sequences contribute to variation that can be subject to natural selection?
Mutations produce genetic diversity which either benefits the organisms or disbenefits them, which leads to natural selection on the favorable mutations
What are the genetic engineering techniques in analyzing or manipulating DNA?
Gel electrophoresis = sorts DNA fragments by size
PCR = duplicates specific DNA fragments
DNA sequencing = determines the nucleotide sequence of the DNA
